Underactive Adrenal Glands/Addison's Disease

Fact

Lack of corticosteroids in the blood may cause the pituitary gland to produce more corticotropin hormones to stimulate the adrenal glands. Since corticotrophin affects melanin production, excess levels of corticotropins may cause dark pigmentation of the skin and lining of the mouth.

What is Addison's disease?

Addison's disease is the result of an underactive adrenal gland. An underactive adrenal gland produces insufficient amounts of cortisol and aldosterone. Cortisol is a steroid hormone that helps to control the body's use of fats, proteins, and carbohydrates, suppresses inflammatory reactions in the body, and affects immune system functions. Aldosterone is a steroid hormone that controls sodium and potassium in the blood. Addison's disease is considered rare. Onset of this disease may occur at any age.

What causes Addison's disease?

Destruction of the adrenal gland due to an autoimmune response is the most common cause of the disease. Some Addison's disease cases are caused by the actual destruction of the adrenal glands through cancer, infection, or other diseases. Other causes may include:

Use of corticosteroids as a treatment, such as prednisone, leading to a slowdown in production of natural corticosteroids by the adrenal glands. (This is sometimes a temporary condition that can be avoided by slowly tapering down the dose of corticosteroid; however, after long-term steroid use, the adrenal gland may have shrunken and no longer be able to produce adequate amounts of corticosteroids.)

Fungal infections

Tuberculosis infection of the adrenal glands

Inherited disorders of the endocrine glands

What results from inadequate corticosteroid production?

Lack of adrenal hormones may cause:

Elevated levels of potassium

Extreme sensitivity to the hormone insulin, which normally is present in the bloodstream (This sensitivity may lead to low blood sugar levels.)

Increased risk during stressful periods, such as surgery, infection, or injury (Corticosteroids play an important role in helping the body fight infection and promote health during physical stress.)

What are the symptoms of Addison's disease?

Mild Addison's disease symptoms may only be apparent when the patient is under physical stress. The following are the most common symptoms of Addison's disease. However, each individual may experience symptoms differently. Symptoms may include:

Weakness

Fatigue

Dizziness

Dark skin

Black freckles

Bluish-black discoloration around the nipples, mouth, rectum, scrotum, or vagina

Weight loss

Dehydration

Lack of appetite

Muscle aches

Nausea

Vomiting

Diarrhea

Intolerance to cold

If not treated, Addison's disease may lead to severe abdominal pain, extreme weakness, low blood pressure, kidney failure, and shock—especially when the patient is experiencing physical stress.

The symptoms of Addison's disease may resemble other conditions or medical problems. Always consult your doctor for a diagnosis.

How is Addison's disease diagnosed?

In addition to a complete medical history and medical examination, diagnostic procedures for Addison's disease may include:

Blood tests to measure corticosteroid hormone levels

Kidney function tests to determine if urine is concentrated

How is Addison's disease treated?

The goal of treatment is to restore the adrenal glands to normal function, producing normal levels of corticosteroid hormones. Specific treatment for Addison's disease will be determined by your doctor based on:

Your age, overall health, and medical history

Extent of the disease

Your tolerance for specific medications, procedures, or therapies

Expectations for the course of the disease

Your opinion or preference

Since Addison's disease can be life threatening, treatment often begins with administration of corticosteroids. Corticosteroids, such as prednisone, may be taken orally or intravenously, depending on the patient's condition. Usually the patient has to continue taking the corticosteroid the rest of his or her life. Treatment may also include taking fludrocortisone, a drug that helps restore the body's normal levels of sodium and potassium.